First paragraph:
In multiparty systems where no party has a majority, policy
influence always comes at a cost in policy purity. A party
has to moderate its own policy principles in order to join
winning coalitions and influence public policy. In this
article I investigate what determines the propensity of a
party to give up some of its policy preferences in exchange
for the power that follows from inter-party agreements. I
show that the policy-seeking behaviour of political parties
is affected by the organizational constraints a party puts
on its representatives in parliament. Moreover, I find that
the organizational impact is moderated by how much the party
needs to compromise to win influence; that is: How serious
the dilemma between purity and influence is.

Figures and
Tables:

Table 1. Behavioural indicators of the pursuit of
policy purity and policy influence

Last Paragraph:
The relationship between intra-party relations and party
behaviour is theoretically underdeveloped and empirically
understudied. The study conducted in this article suggests
that party organization and party objectives are
systematically related and have political consequences, as
they influence party strategies and party behaviour in the
everyday parliamentary work of the parties